Shock absorber



Oct. 20, 1931. w. A. cHRYsT SHOCK ABSORBER Filed Aug. 8, 1930 2 Sheets-Sheet l a/ 5c a 96 7 69/ 52 /Jf/ 6,2 T4 We',

l I l INVENTOR BY W/z/HM f7. c/f/eys w @w Q,

TTORNEYS Oct. 20, 1931. W A1 CHYST 1,828,360

SHO'CK A BSORBER Filed Aug. 8, 1930 2 Sheets-Sheet 2 AT'ToRNEYs Patented Oct. 20, 1931 na rao- STA-'rasV PATENT form-cin Wittmann. OHRYST, OF DAYTON, om assrenoa To nnnoo rnonuors -coRronA'rIom OF DAYTON, OHIO, A CORPORATION O-F DELAWAREV SHOCK ABSORBER Application medraugusjt s,

the'rebound movements of vehicle springs.

Another ob]l ect or the present invention is to provide a double acting hydraulic shock absorber with lluid flow controlling devices of simple structure and design, carried byy the luid displacement member or piston. p

Further objects and advantages of the present` invention will be apparent-.from the 'ollowing description, reference beingY had to the accompanying drawings, wherein a preferred embodiment of one form ofthe a duct40 'extending4 from one end ofthe pis- The ends of this duct are` present invention is clearly shown.

ln the drawings Fig. 'l is a fragmentary side View of `a vehicle chassis, having a shock absorber equipped with the present invention attached thereto. Y u

Fig. 2 is a longitudinal sectional view taken substantially along the line 2 -2 of Fig. 3. u

Fig. 3 is a transverse section taken through the shock absorber intermediate its ends, certain parts being shown inelevation for the salie of clearness.

Fig. 4Vis a fragmentary view of the shock :absorber showing the fluid replenishing valves inthe piston. .e

Fig. 5 isan enlarged,fragmentary, sectional view illustrating one fluid flow controlling device o'ljthe'shocli absorber. y Y

Fig. 6 is a detail sectional view taken sub.- stantially along the line 6--6 of Fig. 5.`

Fig. 7 isV an end view of the piston taken in the direction of the arrows 7-7 of Fig.l 2.

Referring to the drawings, the numeral 20 designates the frame or' thevehicle supported on the axle 2l byA springs 22, only one of whichfis shown. The road wheels of the vey hicle, carried by thefaXle `21, have been omitted for the salie'of clearness. A

` The shock absorber comprises a casing A23 providing a fluid reservoir 24- and 'a cylinder 25. An Opening 26 to the luidreservoir is closedand sealed by the cover cap 2,7. h The o pen ends of lthe cylindery 25 are Y provided 1930. SerialyNo. 473,826.

Y A fluid displacement member `or piston, 31 is reciprocably supported within the cylinder 25 said piston comprising two spacedpiston` head portions 33 and 34 bound together, by a web portion 35. The piston head portion 33 -forms l the spring rebound 4:control chamber 36 at; the end of Vthe-cylinder closed by jcylinder headi28, while the piston headportion=24 l forms the spring Ycompression control charnber 37, at the end of the cylinder-closed by cyl-` inder head 29. Y h i v Referring more particularly to Figs. 2, 3 and 5, it. will be noted that the piston 31 has ton to the, other. enlarged, one opening into the spring rebound chamber and designated by the numeral41 the other enlarged end opening into the springcompression control chamber and being designated by the numeral 42. In the portion 41 of duct 4() aball check-valve 43 is maintained upon the valve-seat 44 by a springV 45 which engages with the cross pin 46. A similar ballfcheck-valve 47 is in the duct por--V tionf42 and isurged upon the valve seat48 by spring 49 resting against cross pin 50. 1t, -may readilylbe seenthat these valves are so constructed that they substantially prevent` fluid,- `from their respective compression chambers, from flowingjinto duct 40,` still fluid frolnsaid duct` may flow pastthese valves into their respective chambers. ,i

The relative spacing of the `piston headv portions 33 and 34, as has beenmentioned,` .provides a niche 52 in the piston intermediate `its ends. The pistonhead .portion 33 has `a ypassage 53 providing communication` between therebound control chamber 36. and the niche 52,1while piston head portion 34 has .a similarpassage 54 between the spring come.

pression controlchamber 37 and said niche.

lIn the end of thepassage; 54, opening into.

the niche 52., a wearpiece 55 is fitted so that .its shank 56`its slidably into thepassage 54.

The opposite endvof lpassage 54, or, `more specifically the endopeninginto the spring compression chamber 37, is interiorly thread- ,m9

ed to receive the fluid flow controlling device or metering block 60. As shown in F ig. 2, this block has a central opening 61 providing a fluid flow orifice. A comparatively stiff coil spring 62 is interposed between the shank 56 of the wear piece 55 and the metering block 60, this spring 62 urging the wear piece toward the center of the niche 52 for purposes to be described.

Piston head portion 33 supports a wear piece 64 the shank 65 ofv which, fits tightly into the end ot the piston head passage 53 opening into the niche 52. This wear piece 64 has its shank 65 recessed as at 66, the recess having rectangular corners 67 provided therein for receiving the rectangular head 68 ot the metering pin 69 so that said metering pin has its head end slidably supported within the shank of the wear piece 64 but not being rotatable relative thereto.

The end of the passage 53, opening into the spring rebound control chamber 36, is interiorly threaded to receive the ring member 70 which provides the annular valve seat 71 within the passage 53. The space in pas- 543 between the ring 70 and theshank 65 of the wear piece may betermed a valve chamber. In this valve chamber valve 75 is provided, this valve being urgedupon the valve sea-t 71 by the spring 76 interposed between the shank of the wear piece of said valve. rlhe valve 75 has a tubular pilot portion 7 7 extending into the ring 7 0, this pilot portion being less in outside diameter than the interior diameter of said ring 70. A cylindrical shank 78 extends from the side of the valve'75 opposite the pilot portion 77, this cylindrical shank portion beingprovided with interior threads for receiving the threaded portion of the metering pin 69.

` The valve 7 and its pilot portion 77 have a central passage providing communication between the chamber 36 and the interior of the cylindrical shank portion 78. A restric- 1 tion in this passage provides the .fluid flow orilice 79into which the tapered end'80 of the metering pin extends. The relative position of the tapered end 80 of the metering pin to the Huid How orifice 79 may be varied by rotation of the valve 75 relative to the pin7 for, as has been mentioned, the one end of the pin 69 is slidably but non-rotatably supported in the shank 65 of the wear piece 64. An opening` 81 is provided in one side of the tubular pilot portion 77 of the valve 75 this opening normally coming within the ring 70 and not communicating with the valve chamber while valve 75 is maintained upon its seat 71. A transverse slot 83 in theend of the pilot portion 77 is adapted to receive a screw driver or any suitable tool by which the valve 75 is turned relative to the pin 69 for purposes of varying the fluid flow through orifice 79 of the valve 75. The cylindrical shank portion 78 of the valve 75 has slots 85 connects the valve chamber in passage 53 75 with the duct 40.

The casing 23 provides two oppositely disposed and aligned bearing portions 92 and v 93 in which the rocker shaft 94 is journaled.

rocker arm 95 is attached shaft 94 within the casing` 23 the round end 96 otl said shaft extending into the niche, 52 of the piston and engaging the wear pieces.- 55 and 64. The wear piece 55 being urge-'QE into engagement with the lever portion 96 by the vspring 62 will likewise urge lever portion 96 int-o engagement with the wear piece 65 so that wear betweenthe lever portion 96 and the wear pieces 55 and 64 automatically compensated for.

The rocker shaft 94 has one end extending from the casing 23, to which i's connected the; shock absorber arm 110. The free end ofthe, arm 110 is swiveliy attached to a connecting link lllwhich is also swivelljyv 'aStcnGd to an anchoring member 112, secured to the axle 21 by a clamping device 113.

Piston head' portion 33 has a passage 100 in which aball cheek valve 101 is urged upon a valve seat in passage by the spring 102. A cross pin 103 provides abutment for one end of the spring 102. A similar passage 105 in the piston head portion 34 contains a ball check-valve 106 urged upon its respective seat by spring 107 which engages the cross pin y108. These two valves 101 and 106 are termed the replenishing valves for the control chambers at their respective ends of the piston, these valves permitting a fiow of fluid l into said chambers to replenish the fluid supply therein.

When the road wheels, not shown, strike an obstruction in the roadway spring 22 will be, compressed and moved toward the frame 20E thereby causing the link 111 to operate the shock absorber arm in a eounterclockwise direction as regards F ig. l. This rotates the rocker shaft 94 in a counterclockwise direction as regards Fig. 4, and thus the piston 31 will be moved toward the right, as regards Figs. 2 and 4. Pressure will now be exerted upon the fluid in the spring compression control chamber 37'. Fluid pressure exerted upon valve 47 assists spring 49 to press said valve tightly upon its seat 48. The fluid in chamber 37 will be forced through the orilice 61 in the metering block 60 into the passage 54 between the block 60 and the wear piece 55. From passage 54 the fluid will flow through cross passage 90 into the duct 40, a 130 .f

to the rocker 80,.

IIS'

zic

fluid from the duct A4l() passesvalve 43 which will now be opened against the effect of its spring 45. This'flow of fluid from the spring compressionlcontrol chamber 37 throughtlie orifice ,61 isrestricted by said orifice, and thus the movement of thepiston 3l towardr the right, ilpon the" spring i compression movementfis resisted, thereby;resistingthe spring compressionmovement i Variations inA the sizeof the orifice 61 will-vary they restriction to the HOW of fluid from chamber 37 to chamber 36 and thusthe resist-ance Vto the movement of the-piston 3l `on itsspring compression control strokeis comparatively resisted. i Y A When the spring 22 has reached the limit of its compression stroke, causedby the striking of the particular obstruction in the roadway, it will return through its rebound stroke to normal load position thus causing the link lll to operate the arm 110 clockwise result-A ing in aclockwise rotation ofthe shaft 94 and its` rocker -lever 95. Now the lpiston 3l will be movedtoward the left as regards Figs. and land pressure will be exerted upon the fluid within the spring rebound control chamber 36. The valve 43 will `be maintained in its closedposition preventing fluid from enteringthe duct l() 4past this valve. The initial How of fluid from the chamber 3G occurs 4"through the orifice 79 in the valve 7 5 past the metering pin portion 8O into the cylindricall `shankftl of the valve, thence through slots 85 in said shank into the valve chamber formedthe passage 53. From the valve chamber the fluid will flow through cross passageQluinto the duct `90, the `fluid from said duct passing into the chamber 37 through the fluid flow orifice 71 and past the valve l? which will now be opened. l If the fluid pressure within the spring rebound compression chamber r36 cannot beproperly relieved by the flow through the orifice 7 9, then this eX- cessive pressure will move the valve 75 against the effect of the spring 7G from engagement with the annular'valve seat 7l, thereby establishing a restricted flow of fluid through the side opening 81 and around the valve 7 5 into the passage 53 from whence the fluid will flow through cross passage 91 into the duct t 240 and into chamber 37 through the orifice 71 and past the now opened valve 47. As the valve 75 is moved against the e'ect of said spring 7 6 the rectangular head 68 of the pin 69 will slide in the wear piece shank 65 thus it may be seen that the metering pin 69 not only controls the flow of Huid through the orifice 79, but it also supports the shank portion 78 of the valve 7 5. Y

From the aforegoing it may be seen that .applicant has provided adouble acting shock absorber of simple structure and design, the

effective operation' of which may be varied by adjustment of the valve or replacement .of the blocki() by one having an orifice of differentsize, or by both adjustment and replacement of the fluid controlling devices.

VV-hile the f-orm of embodiment of the present invention as hereindisclosed, constitutes apreferred form, it is to be understood that otherforms Amight be adopted, all coming g within the scope of the claims which follow. Y

Y WVhat isclaimedis as follows:

l. shockabsorber comprising,in combination a casing providing-a cylinder, fa piston reciprocable in saidcylinder and forming a compression chamber therein, said piston having alpassagefproviding a port for the transfer of fluid from one side of the` piston tothe other; avalve yieldablyurged to close Y.

said port,` said valvehaving a longitudinal passage.; andra metering pin in said valve, for controlling the flow of fluid through the longitudinal passage in the valve, said metering pin providing arsupport for one end of the valve. Y i ,Y Y

-Y 2, A. shock absorber comprising, in combination a casing providing a cylinder, a piston reciprocable in saidcylinder and forming a compression chamber therein, said piston having a. passage providinga port for the transfer of fluid from one side of the piston to the other; a valve; a spring yieldably urging the valve to close the port; a duct in said valve, one portion of which is interiorly threaded, another portion being restricted to provide a fluid flow orifice; and a metering pin supported within the duct in the valve, said pin having a tapered end for controlling the flow of iiuid through the valve orifice, the other end slidably engaging the piston to support the valve, the valve being adjustableroles tatably relative to the pinwhich is not ro- Y tatable relative to the piston. l

3. A; shock absorber comprising, in combination a'casing providing a cylinder; a piston reciprocable in said-cylinder and forming a compression chamber therein, said piston havingA a passage` providing a. port for the transfer offluid from one side of thepiston to ther other; a valve yieldably urged to close` the port, said valve having an orifice adapted to establish a .flow Vof fluid through it and beingimovable. from the port in response to fluid pressure to establish a flow Lof fluid around it, and a metering-,pin threadedly engagingthe valve, said metering pin restricting the flow of fluid through the valve,an-d Y being slidably but non-rotatably carried by the piston, the valve being rotatable relative to the pin to vary the restriction of they flow through theorce. Y y

4,. shock absorber comprising, in Combi- 11a-timexci .Qa-Sina providing a Cylinder; a piston in said cylinder, forming a compression Chamber therein, and having a ductifor the transfer of fluid from one side of the piston to the other; a valve in said duct preventing the flow of iuid from the compression chamber through said duct; a passage through the piston, having an annular valve-seat at its one end; a recessed wear piece fitting into the other end of said passage; a piston operating member engaging the wear piece; a valve in the passage yieldably urged upon the annular valve-seat to close the passage, said valve having a longitudinal passage; a metering pin slidably but non-rotatably supported by the recessed wear piece, threadedly engaging the valve and having a tapering end for restricting the flow of fluid through the longitudinal passage of the valve; and a crosspassage connecting the passage and duct in the piston.

5. A shock absorber comprising, in combination, a casing providing a cylinder, a piston in said cylinder forming a compression chamber therein said piston having a fluid passage therethrough; a pin having one end slidably and n-on-rotatably supported bythe piston, the other end being tapered; a valve having an orifice, said valve being adj ustably supported upon the pin so that the tapered end of the pin extends into the orifice to restrict the flow of fluid therethrough; and a spring urging the valve to close the piston passage.

6. A shock absorber comprising, the combination; a casing providing a cylinder; a piston in said cylinder forming a compression chamber therein said piston having a fluid passage therethrough; two spaced wearpieces carried by the piston in spaced relation; a piston operating member extending between and engaging said wear-pieces; a pin having a rectangular end slidably but non-rotatably supported in the one wear-piece, the other end of the pin being tapered; an oriliced valve screw-threadedly supported upon the pin so that the tapered end of the pin eX- tends into the valve orifice to restrict the flow of fluid therethrough, said valve being rotatably relative to the pin to vary the said restriction to the flow of fluid through its ori-` lice; a spring urging the valve to close the piston passage; and another spring of greater tension than the lirst mentioned spring for urging the second wear-piece against the piston operating member and said member against the first mentioned wear-piece.

7. A double acting shock absorber comprising, in combination, a casing providing a cylinder and a Huid reservoir; a piston in said cylinder forming a compression chamber at each end thereof said piston having a passage for the transfer of fluid from one compression chamber into the other; means for operating the piston; a valve yieldably urged to close one end of the piston passage and being movable in response to pressure to establish a restricted flow of fluid from the compression chamber at its respective end of the cylinder into the compression chamber at the opposite end of the cylinder, said valve having an orifice to establish a constantly restricted flow of fluid between the compression chambers without movement of the valve with regard to the piston; a metering pin screw threadedly carried by the valve and slidably but non-rotatably supported in the piston, said metering pin having a tapered end :tor restricting the flow of fluid through said valve7 the pin being adjustable relative to the valve to vary the restriction to the flow of fluid through said valve, by rotation of the valve relative to said pin; and a constant flow orice in the other end of the piston passage for restricting the How of fluid from the compression chamber adjacent thereto into the compression chamber adjacent the valve.

8. A double acting shock absorber comprising, in combination, a casing providing a cylinder; a piston in said cylinder forming two compression chambers therein said piston having a longitudinal passage providing for the transfer of fluid between the compression chambers; a fluid flow controlling device at one end of the piston for establishing a substantially constantly restricted flow or' fluid through the piston in one direction; a fluid flow controlling device at the other end of the piston adapted lirst to establish a constantly restricted flowl of fluid through the piston in the opposite direction and, in response to increasing fluid pressures another` variably restricted flow in said opposite direction, said last mentioned fluid flow controlling device comprising a spring loaded valve and a metering pin, adjustable by rotation of the valve to alter the constantly restricted flow passage; fluid replenishing valves in the piston; and means for reciprocating the piston within the cylinder.

In testimony whereof I hereto afiix my signature.

WILLIAM A. cHRYsT. 

